Pseudomaryna Australiensis Nov. Gen., Nov. Spec. and Colpoda Brasiliensis Nov

Europ. J. Protistol. 39, 199–212 (2003) © Urban & Fischer Verlag http://www.urbanfischer.de/journals/ejp

Pseudomaryna australiensis nov. gen., nov. spec. and Colpoda brasiliensis nov. spec., two new colpodids (Ciliophora, Colpodea) with a mineral envelope

W. Foissner

Universität Salzburg, Institut für Zoologie, Hellbrunnerstr. 34,A-5020 Salzburg,Austria

Received:20 January 2003; 17 March 2003. Accepted: 27 March 2003

Pseudomaryna australiensis and Colpoda brasiliensis were discovered in floodplain soils from Australia and Brazil and studied in vivo and in silver preparations. They have a common feature, viz., a sheath of clay (mineral) particles embedded in a slimy matrix. Such sheaths, which evolved convergently in various ciliates, are termed “mineral envelopes” and make cells appear like inorganic soil particles, possibly pro- tecting them from predators. The new genus Pseudomaryna belongs to the family Colpodidae and is characterized by the preoral suture which extends for the whole body length right of the oral opening due to the widely projecting left side ciliary rows. Maryna antarctica Foissner, 1993 has the same ciliary pattern and is thus transferred to the new genus: Pseudomaryna antarctica (Foissner, 1993) nov. comb. Both, P. australiensis and P. antarctica are small (length 25–60 µm), reniform soil ciliates differing in the macronuclear structure (with vs. without central nucleolus), the mineral envelope (present vs. absent), and details of the somatic and oral ciliary pattern. Colpoda brasiliensis is also a small ciliate (about 33 × 18 µm), differing from the congeners by the mineral envelope and a combination of ordinary features, viz., the location and structure of the macronucleus and the preoral ciliary pattern. Probably, it is related to the Colpoda steinii group.

Key words: Amazon River floodplain; Australia; Brazil; Colpodea; Murray River floodplain; Pseudomaryna antarctica nov. comb.

Introduction Colpodids are among the best known ciliate alpha-taxonomy, viz., the location and structure of groups due to the detailed monograph by Foissner the macronucleus and preoral suture, and the ar- (1993a), who recognized about 170 species in 55 gen- rangement of the preoral ciliary rows. Further, the era. Since then, 11 new genera and 26 new species mineral envelope is introduced as a new feature for were described, raising the total number of already colpodids in general. It is likely, that additional described colpodids to nearly 200 species (for a brief species can be discriminated by a broad application review, see Foissner et al. 2002). Two further new of these characteristics, provided they are support- species and a new genus are described in the present ed by very accurate and detailed investigations. paper. Twenty-eight species are a considerable gain in 10 years, showing that colpodid diversity is far from being exhausted, which is emphasized by about Materials and methods 15 unpublished, new species in my notebooks. Pseudomaryna australiensis was discovered in soil The two species described in the present paper from the Murray River floodplain in Australia. The highlight several features rarely used in colpodid sample was collected by Mag. Hubert Blatterer in

0932-4739/03/39/02-199 $ 15.00/0 200 W. Foissner

August 1997 and investigated by me in November 1998. ciliary rows, first preoral kinety conspicuously Colpoda brasiliensis was discovered in soil from a small convex because distinctly shortened posteriorly. island in the Amazon River near the town of Manaus, Left oral polykinetid cuneate, composed of an av- Brazil. The sample was collected in November 1996 and erage of 6 ciliary rows. Resting cyst globular and investigated in September 1997. See type location and occurrence sections for details on sites and soils. smooth, covered with the mineral envelope of the The samples were air-dried for about a month and trophic cell. stored in plastic bags. For investigation, they were Type location: Soil from Murray River flood- slightly over-saturated (~120%) with distilled water to plain near the town of Albury, waterside of Ryans obtain a “non-flooded Petri dish” culture, as described road, Australia, 37° S 147° E. in Foissner et al. (2002). Pure culture trials failed. Thus, Type specimens: 1 holotype slide each with sil- material as obtained with the non-flooded Petri dish ver nitrate (Chatton-Lwoff method) and protar- method was used for all investigations. Living cells were gol-impregnated specimens and 4 paratype slides studied using a microscope equipped with a high-power have been deposited in the Biology Centre of the oil immersion objective and differential interference contrast. Silver impregnation and methyl green-pyronin Museum of Upper Austria, Linz (LI), Austria. staining were performed as described in Foissner Relevant specimens are marked by black ink cir- (1991). cles on the cover glass. Counts and measurements on silvered specimens Etymology: Named after the country in which were performed at a magnification of ×1000. In vivo discovered. measurements were conducted at magnifications of Description: Size 35–60 × 20–35 µm, usually × 100–1000. Drawings of live specimens were based on near 45 × 30 µm, slightly flattened laterally, no di- free-hand sketches and micrographs, those of impreg- agonal (postoral) groove (Table 1). Specimens often nated cells were made with a camera lucida. highly refractive, that is, opaque and dark at low Terminology is according to Corliss (1979) and ≤× Foissner (1993a). magnification ( 100) due to the mineral envelope and many compact food vacuoles. Shape basically reniform due to a more or less distinct indentation Results near mid-body, that is, in oral area; in detail, however, highly variable, viz., ellipsoidal (when oral Genus Pseudomaryna nov. gen. bay indistinct), Metopus-like (when broader preorally than postorally), Colpoda maupasi-like Diagnosis: Small, bacteriophagous Colpodidae (when narrower preorally than postorally), or in- with oral opening near mid-body and preorally distinctly dumb-bell-like; rarely fusiform with widely projecting left side ciliary rows, producing very irregular mineral envelope (Figs 1, 2, 5–15, a spatulate (preoral) suture, that is, a bare stripe ex- 18–20, 29–33, 37, 38). Macronucleus in anterior tending from anterior to posterior body end right body half, usually even in anterior dorsal third of of oral opening. Vestibulum of ordinary size, coni- cell, a curious location found in only a few other cal, pharyngeal fibres directed posteriorly. Left colpodids, viz., Dragescozoon terricola, Kreyella wall of vestibulum overhangs right. Right oral minuta, and Orthokreyella schiffmanni (Foissner polykinetid composed of few, slightly disordered 1993a; Foissner et al. 2002); hyaline and thus diffi- kineties. cult to recognize even with interference contrast Type species: Pseudomaryna australiensis nov. optics, except for the more compact central nucle- spec. olus (Figs 1, 2, 3, 11, 39), another rare feature pre- Etymology: Composite of the Greek adjective sent only in Colpoda steinii, C. formisanoi, pseudo (false) and the generic name Maryna. Femi- Dragescozoon terricola, Pseudokreyella terricola, P. nine gender. australis, and Microdiaphanosoma terricola (Foiss- ner 1993a; Foissner et al. 2002). Micronucleus not Description of Pseudomaryna australiensis found. Contractile vacuole in rear body end, with nov. spec. (Figs 1–41, 58; Table 1) single excretory pore in pole centre (Figs 1, 15, 22). Cortex flexible, specific cortical granules (muco- Diagnosis: Size about 45 × 30 µm in vivo. Body cysts) not recognizable, covered by a 1–2 µm thick, reniform and closely covered with a thin mineral brownish “mineral envelope” appearing as a envelope. Macronucleus near dorsal anterior body bright, rough layer separated from pellicle by a end, with single central nucleolus. On average 17 distance of about 0.5 µm in living and prepared New colpodids 201

Figs 1–16. Pseudomaryna australiensis from life (1, 5–12, 16) and after protargol (2, 3), silver carbonate (4), and Chatton-Lwoff silver nitrate (13–15) impregnation. 1: Right side view of a representative specimen packed with food vacuoles containing bacterial rods. Note the mineral envelope and the oral entrance (arrowhead). 2: Ventrolat- eral view of ciliary pattern. Note pharyngeal fibres (arrowhead) and the large, bare area (asterisk) right of the oral opening. 3: Ciliary pattern of ventral side. Note the almost semicircular first preoral kinety (P1) and the four postoral kineties (arrows). 4: Oral ciliary fields. The right field has a row of dikinetids proximally (arrowhead). 5–12: Shape variants with macronucleus shown in figure 11. 12: A fusiform specimen with irregular outline. 13–15: Ventrolateral, right lateral, and left lateral view of ciliary and silverline pattern. Arrowheads mark broad preoral suture with irregularly-meshed silverline pattern. Arrow in figure 15 denotes the excretory pore of the contractile vacuole. 16: The resting cyst is globular and has a smooth wall covered by the mineral envelope of the trophic cell. LP – left oral polykinetid, MA – macronucleus, ME – mineral envelope, OA – oral apparatus, P – preoral kineties, P1 – preoral kinety 1, RP – right oral polykinetid, W – cyst wall. Scale bars 20 µm. 202 W. Foissner cells and with an opening over the oral area (Fig. 1). Mineral envelope compact, composed of 1–2 µm-sized, irregular mineral particles embedded in a slimy matrix to which environmental debris and bacteria adhere and which stains pink with methyl green-pyronin; mineral inclusions similar to clay particles common in the environment and to minute, cytoplasmic crystals conspicuously sparkling under interference contrast optics, quite similar to those shown by Foissner et al. (2002) in micrograph 421y of Maryna namibiensis. Cyto- plasm colourless, in most cells packed with 4–10 µm-sized food vacuoles containing tightly packed bacterial rods or their loosely dispersed indi- gestible remnants (Figs 1, 18–22). Swims rapidly by rotation about main body axis; never rests. Cilia about 8 µm long in vivo, paired, except for barren anterior basal body of dikinetids in rear third; no elongated caudal cilia; arranged in an average of 17 rows more densely ciliated anteriorly Fig. 17. Proposed life cycle of Pseudomaryna australiensis. For explanation, see section on “cysts and life than posteriorly, especially on left side of cell. Cil- cycle”. Note that some details are doubtful, viz., iary rows in Colpoda pattern modified by the whether every fission product forms a resting cyst after genus-specific, spatulate preoral suture, which is growth, or can undergo another round of division be- not above but right of oral opening and thus ex- fore resting encystment.

Table 1. Morphometric data on Pseudomaryna australiensis.

Characteristics1 Method2 xMSD¯ SE CV Min Max n

Body, length CHL 40.8 41 3.3 0.7 8.1 36 47 21 Body, width in lateral view CHL 26.5 27 2.8 0.6 10.5 22 32 21 Body, width in ventral or dorsal view CHL 20.1 20 1.8 0.4 8.9 17 24 21 Anterior body end to macronucleus, distance P 5.3 5 3.5 0.8 66.9 1 17 21 Anterior body end to summit of CHL 16.6 17 1.9 0.4 11.7 13 20 21 first preoral kinety, distance Anterior end to posterior margin CHL 25.1 25 2.0 0.4 7.9 22 28 21 of left oral polykinetid, distance Macronucleus, length P 9.3 10 1.7 0.4 18.1 6 13 21 Macronucleus, width P 6.0 6 0.7 0.2 11.8 5 7 21 Right oral polykinetid, length P 5.4 5 0.6 0.2 11.1 5 7 20 Left oral polykinetid, length P 4.0 4 0.4 0.1 9.7 3 5 21 Left oral polykinetid, width P 2.8 3 – – – 2 3 21 Left oral polykinetid, number of ciliary rows P 6.1 6 – – – 6 7 21 Somatic ciliary rows, total number CHL 16.9 17 1.1 0.3 6.7 15 19 21 Postoral ciliary rows, number CHL 4.0 4 0 0 0 4 4 21 Kinetids in first row right of suture, number CHL 11.0 12 1.7 0.4 15.8 8 13 21 Kinetids in first preoral kinety, number CHL 11.8 12 1.1 0.3 9.5 10 14 21 Kinetids in fourth preoral kinety, number CHL 20.1 20 2.5 0.6 12.5 17 25 21 Resting cysts, diameter without mineral envelope IV 26.3 27 2.4 0.6 9.3 22 30 18

1Data based on randomly selected specimens from a non-flooded Petri dish culture. Measurements in µm. CV – coefficient of variation in %, M – median, Max – maximum, Min – minimum, n – number of individuals investigated, SD – standard deviation, SE – standard error of arithmetic mean, x¯ – arithmetic mean. 2 CHL – silver nitrate impregnation after Chatton-Lwoff, as described in Foissner (1991), IV – in vivo, P – protargol impregnation, protocol A in Foissner (1991). New colpodids 203

Figs 18–28. Pseudomaryna australiensis, trophic cells (18–24) and resting cysts (25–28) from life. 18, 19: Right side and dorsal view of a specimen packed with food vacuoles. The oral bay (arrowhead) produces the reniform shape of the organism, which is slightly flattened laterally (19). The rough surface is produced by the mineral envelope. 20, 21: Right lateral view of a Metopus-shaped specimen in the bright field and interference contrast microscope, where some of the mineral particles of the envelope are highly refractive (arrowheads). 22–24: Optical section (22) and surface views (23, 24) of a specimen with many food vacuoles containing tightly packed bacteria. The rough surface is caused by the mineral envelope, that is, a 1–2 µm thick, slimy coat containing organic debris, bacteria, and 1–2 µm-sized mineral particles, some being highly refractive in the interference contrast microscope (arrowheads). 25, 26: Resting cysts showing the thin (1–2 µm), but compact mineral envelope. 27: Resting cyst separated from its mineral envelope by slight cover glass pressure. 28: When squashed, the cyst content (cell) flows out, leaving behind the strongly refractive cyst wall and mineral envelope. B – bacteria in mineral envelope, C – cilia, CO – ciliate cortex, CV – contractile vacuole, EB – environmental bacteria, FV – food vacuoles, ME – mineral envelope, W – cyst wall. Scale bars 20 µm. 204 W. Foissner

Figs 29–41. Pseudomaryna australiensis, body shape and ciliary and silverline pattern after silver nitrate (29–38) and silver carbonate (39–41) impregnation. Length of specimens 36–47 µm. 29–33: Right lateral (29, 30), ventral (31, 32), and left lateral (33) overviews. Arrows mark preoral kinety 1; arrowheads denote spatulate preoral suture; asterisks mark oral apparatus. 34–36: Ventrolateral, ventral, and left lateral views showing, inter alia, the preoral suture (arrowhead) and the beginning of the leftmost postoral kinety (arrow). 37, 38: Optical sections showing body shape and location of oral apparatus. 39–41: Ventral overview and details of oral ciliary pattern. Arrows mark the four postoral kineties. Arrowhead in figure 40 denotes row of dikinetids at proximal margin of right ciliary field. LP – left oral polykinetid, MA – macronucleus, OA – oral apparatus, P1 – preoral kinety 1, RP – right oral polykinetid. New colpodids 205 tends, as spatula-handle, to posterior body end be- resting cyst after some growth, or can undergo an- tween right side and postoral kineties (Figs 1–3, other round of division before resting encystment. 13–15, 22, 23, 30–39; Table 1). Right side ciliary Pseudomaryna australiensis divides exclusively rows indistinctly sigmoidal, first two to three rows in thin-walled reproductive cysts with up to four slightly shortened anteriorly producing, together offspring, and produces thick-walled resting cysts, with the gradually shortened left side preoral rows, as common in small colpodids (Foissner 1993a). a roundish, bare anterior pole area, that is, the spat- Both cyst types retain the brownish mineral enve- ula of the preoral suture. Preoral ciliary rows con- lope of the trophic cell, but cyst and envelope can spicuous because numerous and distinctly convex, be separated by mild cover glass pressure (Fig. 27). extend transversely over ventral side and spiral Resting cysts globular and 26 µm across on aver- posteriorly on left and dorsal side of cell; first pre- age, wall colourless, smooth, and about 1 µm thick; oral kinety above oral opening especially distinct cytoplasm with some 2–3 µm-sized crystals and because very densely ciliated and almost semicir- many opaque globules 1–5 µm across (Figs 16, 17, cular, that is, shortened postorally. Invariably four 25–28; Table 1). postoral ciliary rows, leftmost and rightmost row Pseudomaryna australiensis becomes abundant extend to upper mouth margin almost touching already 20–30 h after rewetting the sample and en- first preoral kinety, oral area thus surrounded by a cysts after one or two days, even if the sample is key-hole shaped kinety pattern. undisturbed. The same has been observed in some Oral apparatus in flat indentation slightly under- marynid colpodids from temporary pools (for a neath mid-body, posterior margin of left ciliary review, see Foissner 1993a, p. 337). This indicates field 62% distant from anterior body end on aver- that P. australiensis has a marynid life cycle and is age (Figs 1–3, 13, 14, 18, 29–35, 37–39; Table 1). an r-selected organism, as are colpodids in general Vestibulum broadly conical and small, that is, (Foissner 1993a), adapted to the floodplain envi- about 6 µm wide and deep, a bundle of pharyngeal ronment in that it quickly excysts and reproduces fibres originates at proximal end and extends to when the flood comes, and encysts when other or- rear body end. Left oral polykinetid cuneate, com- ganisms and potential predators become abundant; posed of an average of six slightly convex rows be- the mineral envelope may be an additional shelter coming longer distally; cilia only about 3 µm long (see discussion). and thus not forming a beard as in Colpoda steinii. Right oral polykinetid crescentic, composed of Colpoda brasiliensis nov. spec. four slightly disordered kineties and a row of about (Figs 42–57; Table 2) 10 dikinetids proximally (Figs 1–4, 39–41; Table 1). Silverline pattern colpodid throughout, irregu- Diagnosis: Size about 33 × 18 µm in vivo. Body larly meshed only in bare regions, that is, in preo- covered with a mineral envelope and Colpoda ral suture and around excretory pore of contractile maupasi-shaped, that is, reniform with anterior vacuole. A tree-shaped silverline pattern extends in half narrower than posterior. Macronucleus usual- left vestibular wall (Figs 13–15, 34–37). ly in posterior dorsal quadrant of cell, ellipsoidal, Occurrence: As yet found only at type location, with single central nucleolus. On average 12 ciliary where it was abundant already one day after rewet- rows, distance between first and second row right ting. The site, which is used as a cattle pasture, is of oral opening distinctly widened anteriorly; flooded for months in wet years. The sample was a number of preoral kineties thus higher at left than mixture of almost black, humic top soil, many fine right side. Oral apparatus in second quarter of cell, roots, and Myriophyllum and Valisneria litter; it left polykinetid composed of about 5 kineties be- had pH 5.2 (in water) and contained more than 100 coming slightly longer distally. ciliate species, of which many were undescribed. Type location: Clayic top soil from a small is- Cysts and life cycle: Unfortunately, pure culture land in the Amazon River near Manaus, Brazil, trials failed. Thus, all observations and the proposed 04° S 60° W. life cycle (Fig. 17) are from specimens as obtained Type specimens: 1 holotype and 1 paratype slide with the non-flooded Petri dish culture, which was with protargol-impregnated trophic and cystic air-dried and rewetted three times to simulate the specimens have been deposited in the Biology flood-pulses typical for the habitat. Accordingly, Centre of the Museum of Upper Austria in Linz the life cycle could be not elucidated in full detail, (LI), Austria. Relevant specimens are marked by for instance, whether every fission product forms a black ink circles on the cover glass. 206 W. Foissner

Etymology: Named after the country in which for the small central nucleolus, which stains red discovered. with methyl green-pyronin and impregnates rather Description: When I first saw this species, it was intensely with protargol; micronucleus not un- rather abundant but misidentified as a “small, dirty equivocally identified, probably attached to variety of C. maupasi”. Two weeks later, when I macronucleus and ellipsoidal (Figs 42, 43, 45, 47, recognized it as a distinct species, it was already 49–51; Table 2). Contractile vacuole in centre of rear rare. Thus, the morphometric data are incomplete. body end. Cortex flexible, special cortical granules Further, the protargol preparations are of only (extrusomes) recognizable neither in vivo nor with mediocre quality because the mineral envelope im- methyl green-pyronin stain. Mineral envelope 1–3 pregnates rather intensely and hides the ciliary pat- µm thick, composed of clay particles up to 3 µm in tern. Thus, the description should be refined by sized embedded in a slimy matrix to which environ- observations on other populations. mental organic debris and bacteria may adhere; Size 30–40 × 15–25 µm in vivo, usually about 33 × stains bluish with methyl green-pyronin and pro- 18 µm. Invariably Colpoda maupasi-shaped, that is, vides cells with a rough, dirty surface (Figs 42, reniform with flat oral indentation above mid-body 47–54). Cytoplasm colourless, usually packed with and narrowed anterior half; no diagonal (postoral) food vacuoles 5–10 µm across and with many groove (Figs 42, 45, 47, 49; Table 2). Macronucleus minute crystals conspicuously sparkling under in- in rear half of cell, usually in posterior dorsal quad- terference contrast optics, as in many other small rant, about 7 × 5 µm and very hyaline in vivo, except colpodids and marynids (Foissner et al. 2002).

Figs 42–46. Colpoda brasiliensis from life (42) and after protargol impregnation (43–46). 42: Right side view of a representative, C. maupasi-shaped specimen. Note the rough surface caused by the mineral envelope. 43, 45, 46: Ciliary pattern of ventral side and of right and left side of holotype specimen. Note the circular vestibular opening (VO) and the two specific features of the ciliary pattern, viz., the increased distance between the anterior portion of the two first right side kineties (asterisks) and the intercalated left side kineties (arrowheads). This pattern is different from that of C. maupasi, which resembles C. brasiliensis in the shape of the body and the oral ciliary fields (Figs 61–66). 44: Resting cyst covered by the mineral envelope of the trophic cell. LP – left oral polykinetid, MA – macronucleus, ME – mineral envelope, N – central nucleolus of the macronucleus, RP – right oral polykinetid, S – preoral suture, VO – vestibular opening, W – cyst wall. Scale bars 15 µm. New colpodids 207

Figs 47–57. Colpoda brasiliensis, trophic cells (length 30–40 µm) in vivo (47–54) and resting cysts after protargol impregnation (55–57). Arrows mark mineral particles of the mineral envelope. 47, 49, 50, 51, 53: Right (49, 51, 53) and left (47, 50) side views of slightly squeezed (by cover glass) specimens showing the main organelles. Arrowhead in figure 47 denotes oral bay. 48, 52, 54: Ventral surface views of a strongly flattened (by cover glass pressure) specimen to show the oral structures and the mineral envelope. 55–57: Resting cysts, 17–37 × 13–26 µm. CV – contractile vacuole, FV – food vacuoles, LP – left oral polykinetid, MA – macronucleus, ME – mineral envelope, MI? – sup- posed micronucleus, N – nucleolus, OA – oral apparatus, RP – right oral polykinetid, W – cyst wall. 208 W. Foissner

Feeds on bacteria, whose compact spores become three postoral kineties, leftmost kinety slightly distinct in late food vacuoles (Figs 42, 47, 49, 53). shortened anteriorly. Crawls clumsily on soil particles, but may also Oral apparatus small and thus inconspicuous, in rapidly glide on microscope slide. flat indentation of second quarter of cell, posterior Cilia about 10 µm long in vivo, paired, except in margin of left ciliary field on average 43% distant rear body portion, where only the dikinetid’s pos- from anterior body end (Figs 42, 43, 45, 47, 49; terior basal body is ciliated; no elongated caudal Table 2). Vestibulum conical, about 6 µm wide and cilia; arranged in an average of 12 rows, more deep, vestibular opening and oral ciliary fields densely ciliated anteriorly than posteriorly. Ciliary form conspicuous, circular pattern (Fig. 43); pha- rows in typical Colpoda pattern with, however, ryngeal fibres not impregnated. Left oral some specializations; abut preorally, except for polykinetid indistinctly cuneate, composed of an three postoral kineties, forming narrow suture ex- average of five slightly convex rows becoming tending from anterior pole to summit of oral open- slightly longer distally, cilia of proximal rows ing (Figs 43, 45, 46; Table 2). Right side ciliary about 3 µm long, those of distal rows 5 µm, do not rows slightly sigmoidal, distance between first and form a distinct beard as in Colpoda steinii. Right second row right of oral opening conspicuously oral polykinetid semicircular, probably composed widened anteriorly. Left side ciliary rows rather of three or four rows of cilia projecting about 5 µm distinctly sigmoidal, more narrowly spaced than from vestibular margin (Figs 42, 45, 48, 49, 52). right side rows along preoral suture, producing a Cysts: Resting cysts observed only in protargol special pattern in that an additional row is interca- slides, globular to broadly ellipsoidal, about 24 × lated between each two right side rows. Invariably 22 µm on average (Table 2). Wall up to 2.5 µm thick

Table 2. Morphometric data on Colpoda brasiliensis.

Characteristics1 xMSD¯ SE CV Min Max n

Body, length 29.4 28.5 3.4 1.1 11.5 26 37 10 Body, width in lateral view 16.5 15.5 3.0 1.0 18.4 13 22 10 Anterior body end to macronucleus, distance 17.4 17.0 2.8 0.9 15.8 14 22 10 Anterior body end to right polykinetid, distance 7.8 8.0 0.7 0.2 8.6 7 9 9 Anterior body end to posterior margin of left 12.7 13.0 – – – 12 13 9 oral polykinetid, distance Macronucleus, length 6.3 6.0 1.1 0.3 16.8 5 8 10 Macronucleus, width 4.4 4.0 0.5 0.2 11.7 4 5 10 Right oral polykinetid, length 4.3 4.0 – – – 4 5 4 Left oral polykinetid, length 3.2 3.0 – – – 3 4 5 Left oral polykinetid, width 1.9 2.0 – – – 1 2 5 Left oral polykinetid, number of ciliary rows 4.8 5.0 – – – 4 5 5 Somatic ciliary rows, total number 12.2 12.0 – – – 12 13 5 Postoral ciliary rows, number 3.0 3.0 0.0 0.0 0.0 3 3 6 Kinetids in first ciliary row right of oral opening, 12.5 12.0 1.7 0.9 13.9 11 15 4 number Resting cysts, total length2 24.3 21.0 7.6 1.7 31.1 17 37 21 Resting cysts, total width2 21.6 20.0 8.0 1.7 37.0 13 36 21 Resting cysts, length of cell 15.1 13.0 3.2 0.7 21.0 11 22 21 Resting cysts, width of cell 13.1 13.0 4.1 0.9 31.0 7 22 21 Resting cysts, macronucleus length 5.3 5.0 0.9 0.2 17.4 4 7 21 Resting cysts, macronucleus width 4.9 5.0 0.6 0.1 13.1 4 6 21

1Data based on mounted, protargol-impregnated (protocol A in Foissner 1991), and randomly selected specimens from a non-flooded Petri dish culture. Measurements in µm. CV – coefficient of variation in %, M – median, Max – maximum, Min – minimum, n – number of individuals investigated, SD – standard deviation, SE – standard error of arithmetic mean, x¯ – arithmetic mean. 2With wall and mineral envelope. New colpodids 209 and not impregnated, covered by the brownish- stripe extends whole body length to the right of impregnated mineral envelope of the trophic cell, the oral apparatus (Fig. 58), while the preoral su- providing cysts with a rough, irregular surface. ture is narrower and extends between the anterior Central nucleolus of macronucleus distinct (Figs end of the body and the oral opening in Colpoda 44, 55–57). and most marynids (Figs 59, 60). Occurrence and ecology: As yet found only at Maryna antarctica Foissner, 1993a has a very type location, where it was moderately abundant similar mouth location and somatic ciliary pattern one week after rewetting the sample, which had pH as P. australiensis, and is thus transferred to the 5.1 (in water) and was a mixture of clayic soil, fine new genus: Pseudomaryna antarctica (Foissner, roots, and leaf litter from the top 1 cm. The site rep- 1993) nov. comb. Unfortunately, the transfer is not resents one of the typical small islands found in the entirely certain because the direction of the pha- Amazon River and is flooded annually. ryngeal fibres is not recognizable in the slides of M. antarctica.

Discussion Pseudomaryna australiensis and Pseudomaryna as a new genus Colpoda brasiliensis as new species Colpodids with a mineral envelope have not The generic diagnosis of Pseudomaryna has been described previously (Foissner 1993a; Foiss- been written to conform with the monograph of ner et al. 2002). Thus, P. australiensis and C. bra- Foissner (1993a), the last reviser of the group. At siliensis are very distinct species, easy to recognize first glance, Pseudomaryna appears as a member of even without silver impregnation and interference the Marynidae because both the trophic cells and contrast optics (Figs 18, 20, 47, 49). They differ the resting cysts have a kind of tectinic case (“min- from each other, inter alia, by body shape (Colpo- eral envelope”), as is typical for many species of da cucullus-like vs. Colpoda maupasi-like), the lo- this family (for a review, see Foissner 1993a). Fur- cation of the macronucleus (in anterior vs. posteri- ther, the life cycle of P. australiensis is likely more or body end), and the somatic ciliary pattern (Figs similar to that of common marynids than to colpo- 2, 3, 43, 45). dids (Fig. 17), and the preoral suture and ciliary Pseudomaryna australiensis differs from Mary- pattern of the marynid genus Ilsiella basically na antarctica Foissner, 1993a, combined with matches that of P. australiensis (Foissner 1993a). Pseudomaryna above, by body size (35–60 × 20–35 However, the main features of the marynids, viz., µm vs. 25–35 × 20–25 µm), the structure of the the posteriorly located oral opening and the anteri- macronucleus (with vs. without central nucleolus), orly directed pharyngeal fibres are not found in P. the mineral envelope (present vs. absent), the num- australiensis, which has the oral opening at or ber (about 17 vs. 11) and arrangement of the ciliary slightly underneath mid-body and the pharyngeal rows (first preoral kinety conspicuous vs. incon- fibres directed posteriorly (Figs 1, 2, 18), as have all spicuous; second and third preoral kinety in paral- “good” members of the family Colpodidae (Foiss- lel vs. V-like spread anteriorly), and the structure ner 1993a). Thus, Pseudomaryna most likely of the left oral polykinetid (composed of an aver- evolved the marynid features convergently and be- age of 6 vs. 8 rows becoming longer vs. shorter dis- longs to the family Colpodidae, as defined by tally). These constitute quite a number of differ- Foissner (1993a). This is emphasized by Colpoda ences, suggesting that further species exist. Of brasiliensis, a typical Colpoda species, except for course, P. australiensis resembles several small the mineral envelope, which is similar to the tec- Colpoda species, especially small-sized specimens tinic case of the Marynidae. of the Colpoda cucullus group, which have a simi- Pseudomaryna differs from the colpodid genera lar body shape as the specimen of P. australiensis described in Foissner (1993a, b, c) and Foissner et shown in figure 18. However, all Colpoda spp. lack al. (2002) mainly by the ciliary pattern: the left side a mineral envelope and have a different ciliary pat- preoral kineties extend to the right side of the cell tern (Figs 60–66 and Foissner 1993a). causing the preoral suture to become located to the Colpoda brasiliensis highly resembles small spec- right of the oral opening and to continue into the imens of Colpoda maupasi, one of the most fre- postoral body region. Thus, a broad, unciliated quent soil ciliates (Foissner 1993a; Foissner et al. 210 W. Foissner New colpodids 211

2002), but is easily distinguished from that species forerunner of the slimy case inhabited by many cil- by the mineral envelope (present vs. absent), the iates, including several colpodids (for reviews, see structure of the macronucleus (with vs. without Corliss 1979 and Foissner 1993a). Mineral en- central nucleolus), the arrangement of the preoral velopes are known also from other ciliates, for in- ciliary rows (cp. Figs 43, 45, 61–66), and the num- stance, the peritrichs Geleiella vagans Stiller, 1939 ber of somatic ciliary rows (about 12 vs. 15–40, and Zoothamnium kentii Grenfell, as redescribed usually 20–30; Figs 61–66 and Foissner 1993a) and by Foissner et al. (1992); the cyrtophorid Atopo- kineties comprising the left oral polykinetid (about chilodon arenifer Kahl, 1933; the oligotrich Strobi- 5 vs. 9–10). Several populations of C. steinii, C. lidium minimum Gruber, as redescribed in Kahl formisanoi, and Dragescozoon terricola also resem- (1932); and the karyorelictid Ciliofaurea arenicola ble C. brasiliensis, especially in body size and Dragesco, 1960. Obviously, mineral envelopes shape, the location and structure of the macronu- evolved independently several times. This is why I cleus, and the preoral ciliary pattern. However, all do not lump together P. australiensis and C. bra- C. steinii populations have a highly characteristic, siliensis in a separate genus. Likewise, the feature is spoon-shaped, comparatively large left oral probably useful only for defining species, not gen- polykinetid, conspicuously different from the rect- era, because enveloped species are frequently very angular or slightly cuneate, minute polykinetid of similar to their ordinary congeners in most other C. brasiliensis; all C. formisanoi populations have characteristics, as shown by Colpoda brasiliensis an acute posterior body end, distinctly different and Geleiella vagans, which Dingfelder (1962) from the broadly rounded end of C. brasiliensis; and, later, also Stiller (1971) and Foissner (1977) and Dragescozoon terricola has the macronucleus transferred to Astylozoon. in the anterior body end and a somewhat different Generally, however, mineral envelopes are much preoral ciliary pattern. Of course, all these species, rarer than slimy cases or compact loricas. It is like- described in detail in Foissner (1993a) and Foissner ly, that mineral envelopes are not simple progeni- et al. (2002), lack a mineral envelope. On the other tors of slimy cases because case-building ciliates hand, they have conspicuous similarities suggesting are never covered by mineral particles, not even a common ancestor and resurrecting the genus during case construction, although later often Paracolpoda Lynn, 1978. Probably, C. brasiliensis is some mineral particles adhere to the slimy case more closely related to the Colpoda steinii group surface. Accordingly, the mineral particles of the than to the C. maupasi group, with which it shares envelope of Pseudomaryna, Colpoda, and other mainly body shape. ciliates are most likely actively searched for and attached to the body surface by a slimy substance. The mineral envelope, a distinct type of sheath Stiller (1939) and Dingfelder (1962) already sug- in ciliates, and its proposed protective function gested a protective function for the mineral envelopes and slimy cases because they occur rather The mineral envelope of Pseudomaryna aus- frequently in ciliates living in ephemeral, often tur- traliensis and Colpoda brasiliensis appears as a bid puddles. Both, P. australiensis and C. brasilien- rather inconspicuous structure and as a simple sis occur in very fine-grained floodplain soils.

Figs 58–60. Comparison of the ciliary pattern of Pseudomaryna, Maryna, and Colpoda (based on Foissner 1993a). The most conspicuous difference concerns the preoral suture (S, in black), which extends from the anterior body end to the summit of the oral opening in Maryna (59) and Colpoda (60), while right of the oral opening and whole body length in Pseudomaryna (58). OA – oral apparatus, S – preoral suture. Figs 61–66. Ciliary pattern of Colpoda maupasi populations from Venezuela (61), various sites of Namibia (62, 63, 65, 66), and Costa Rica (64) after Chatton-Lwoff silver nitrate (61, 62, 64) and silver carbonate (63, 65, 66) impregnation. The ciliary pattern of C. maupasi is obviously very similar in populations globally (see Foissner 1993a for further figures), but slightly different from that of C. brasiliensis, although both species largely agree in the shape of the body and oral ciliary fields (cp. Figs 42, 43, 45, 46). The ciliary rows are narrowly spaced at both sides of the preoral suture in C. maupasi, while the right side rows are wider spaced than the left side rows in C. brasiliensis. This causes a different preoral ciliary pattern: a ciliary row each at the right and left side abuts in C. maupasi, while an additional row is intercalated in C. brasiliensis (Figs 43, 45; arrowheads). LP – left oral polykinetid, MA – macronucleus, RP – right oral polykinetid. 212 W. Foissner

When looking at these ciliates in a drop of flood- Foissner W. (1977): Revision der Genera Astylozoon (Engel- plain water, they appear like soil particles. Thus, I mann) und Hastatella (Erlanger) (Ciliata Natantina). Pro- tistologica 13, 353–379. suggest that the envelope greatly decreases the Foissner W. (1991): Basic light and scanning electron micro- probability of being recognized by predators as a scopic methods for taxonomic studies of ciliated protozoa. latent food source. This applies also to the resting Europ. J. Protistol. 27, 313–330. cysts, which take over the envelope of the trophic Foissner W. (1993a): Colpodea (Ciliophora). Protozoenfauna 4/1, X + 798 pp. cell (Figs 16, 25–28, 44, 55–57). Alternatively, the Foissner W. (1993b): Idiocolpoda pelobia gen. n., sp. n., a new envelope could protect the inhabitants from being colpodid ciliate (Protozoa, Ciliophora) from an ephemeral injured by swirling mineral particles, which often stream in Hawaii. Acta Protozool. 32, 175–182. have sharp edges. Foissner W. (1993c): Corticocolpoda kaneshiroae n.g., n. sp., a new colpodid ciliate (Protozoa, Ciliophora) from the bark of Ohia trees in Hawaii. J. Euk. Microbiol. 40, 764–775. Acknowledgements: This study was supported Foissner W., Berger H. and Kohmann F. (1992): Taxonomi- sche und ökologische Revision der Ciliaten des Saprobien- by the Austrian Science Foundation. The technical systems Band II: Peritrichia, Heterotrichida, Odonto- assistance of Dr. Eva Herzog and Dr. Brigitte Moser is stomatida. Informationsberichte des Bayer. Landesamtes greatly acknowledged. für Wasserwirtschaft 5/92, 1–502. Foissner W., Agatha S. and Berger H. (2002): Soil ciliates (Pro- tozoa, Ciliophora) from Namibia (Southwest Africa), with emphasis on two contrasting environments, the References Etosha Region and the Namib Desert. Denisia 5, 1–1459. Kahl A. (1932): Urtiere oder Protozoa I: Wimpertiere oder Corliss J. O. (1979): The ciliated protozoa: characterization, Ciliata (Infusoria) 3. Spirotricha. Tierwelt Dtl. 25, 399–650. classification and guide to the literature. 2nd ed. Pergamon Kahl A. (1933): Ciliata libera et ectocommensalia. Tierwelt Press, Oxford, New York, Toronto, Sydney, Paris, Frank- N.- und Ostsee 23 (Teil II. c3), 29–146. furt. Lynn D. H. (1978): Comparative ultrastructure and systemat- Dingfelder J. H. (1962): Die Ciliaten vorübergehender ics of the Colpodida. Diss. Abstr. Int. 38, no. 9, 2 pp. Gewässer. Arch Protistenk. 105, 509–658. Stiller J. (1939): Eine neue Gattung der Ordnung Peritricha. Dragesco J. (1960): Ciliés mésopsammiques littoraux. Systé- Geleiella vagans gen. n. sp. n. Acta Univ. szeged. 5, 53–56. matique, morphologie, écologie. Trav. Stn. biol. Roscoff Stiller J. (1971): Szájkoszorús csillósok – Peritricha. Fauna (N.S.) 12, 1–356. Hung. 105, 1–245 (in Hungarian).